28181448 has 48 divisors (see below), whose sum is σ = 76908780. Its totient is φ = 9321984.

The previous prime is 28181429. The next prime is 28181453. The reversal of 28181448 is 84418182.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 27688644 + 492804 = 5262^2 + 702^2 .

It is a super-2 number, since 2×28181448² = 1588388022753408, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8436 + ... + 11292.

Almost surely, 2^28181448 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28181448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38454390).

28181448 is an abundant number, since it is smaller than the sum of its proper divisors (48727332).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28181448 is a wasteful number, since it uses less digits than its factorization.

28181448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3006 (or 2999 counting only the distinct ones).

The product of its digits is 16384, while the sum is 36.

The square root of 28181448 is about 5308.6201597025. The cubic root of 28181448 is about 304.3134175285.

It can be divided in two parts, 28 and 181448, that added together give a square (181476 = 426²).

The spelling of 28181448 in words is "twenty-eight million, one hundred eighty-one thousand, four hundred forty-eight".